-al a-a a-b a-c aaa aab aac aad aak aal aas ab- aba abb abc abd abk abl abs ac- aca acb acc acd ack acl acs ad- ada adb adc add adk adl ads aka akb akc akd akk akl aks al- ala alb alc ald alk all als as- asa asb asc asd ask asl ass baa bab bac bad bak bal bas bba bbb bbc bbd bbk bbl bbs bca bcb bcc bcd bck bcl bcs bda bdb bdc bdd bdk bdl bds bka bkb bkc bkk bkl bks bla blb blc bld blk bll bls bsa bsb bsc bsd bsk bsl bss c-- caa cab cac cad cak cal cas cba cbb cbc cbd cbk cbl cbs cca ccb ccc ccd cck ccl ccs cda cdb cdc cdd cdk cdl cds cka ckb ckc ckd cks cl- cla clb clc cld clk cll cls csa csb csc csd csk csl css daa dab dac dad dak dal das dba dbb dbc dbd dbk dbl dbs dca dcb dcc dcd dck dcl dcs dda ddb ddc ddd ddk ddl dds dka dkb dkc dkk dkl dks dl- dla dlb dlc dld dlk dll dls dsa dsb dsc dsd dsk dsl dss ka- kaa kab kac kad kak kal kas kba kbb kbc kbd kbk kbl kbs kca kcb kcc kcd kck kcl kcs kda kdb kdc kdk kdl kds kkb kkc kkk kkl kks kl- kla klb klc kld kls ksa ksb ksc ksd ksk ksl kss la- laa lab lac lad lak lal las lba lbb lbc lbd lbk lbl lbs lca lcb lcc lcd lck lcl lcs lda ldb ldc ldd ldk ldl lds lka lkb lkl lks lla llb llc lld llk lll lls lsa lsb lsc lsd lsk lsl lss saa sab sac sad sak sal sas sba sbb sbc sbd sbk sbl sbs sca scb scc scd sck scl scs sda sdb sdc sdd sdk sdl sds sk- ska skb skc skd skk skl sks sla slb slc sld slk sll sls ss- ssa ssb ssc ssd ssk ssl sss

a-ak aaaa aaab aaac aaad aaal aaas aaba aabb aabc aabd aabl aaca aacb aacc aacd aack aacl aacs aada aadc aads aaka aala aalc aald aall aals aasa aasc aasd aass abaa abab abac abad abak abal abas abb- abba abbb abbs abca abcb abcc abcd abcl abcs abda abla abls abs- absa absd absl abss acaa acab acac acad acas acba acbl acca accc accd accs acda acdb acdc acds ackd acks acla aclc acls acsa acsc acsd acsl acss adaa adab adac adad adak adal adas adba adbc adcc adcs adda addc addd addl adds adls adsa adsl adss akaa akal akas akca akka aksa alaa alac alad alak alal alas alb- alba albc albs alca alcc alcs ald- alda aldl alds alk- alka alkb alkd all- alla alll alls alsa alsc asaa asab asac asad asak asal asas asba asc- asca ascb ascc ascl asda asdl asds aska asks asla assa assc assd assk assl asss baaa baad baak baal baas baba babb babs bac- baca bacc back bacs bada badb badd bads bak- baka bakl baks bala balc bald balk ball bals basa basc bask bass bbad bbas bbbb bbbs bbdd bblb bbls bcaa bcas bcbc bcbs bcca bccc bccl bccs bcda bcds bcsa bcsc bcsl bcss bdbc bddc bdls bdsd blaa blab blac blad blak blas bldc blkb blkd blls blss bsaa bsac bsas bsbd bscs bsdl bslc bssc bssd c-cd caaa caab caac caal caas caba cabs cac- caca cacc cack cada cadc cadd cads caka cala calc cald calk call cals casa casb casc casd cask casl cass cbac cbal cbbc cbbs cbca cbcc cbcl cbcs cbdb cbdc cbds cbka cbkl cblb cblc cbsa cbsc ccaa ccab ccac ccad ccas ccba ccbc ccca cccb cccc cccl cccs ccdc ccds ccla cclc ccls ccsa ccsd ccsl ccss cdaa cdac cdad cdba cdcs cdda cddb cddl cdls cdss ckac ckbc ckck ckcl ckcs cksa cksb cksl clab clad clas clcd cldc clsa clsc csaa csab csac csak csas cscb cscc cscd cscl cscs csda csdb cska csks csla csld cssa cssd daab daad daal daas daba dabb dabs daca dacs dada dads daka daks dala dalk dall dals dasa dasb dasc dasd dask dasl dass dbas dbcc dbcs dbls dbsa dbss dcas dcbc dcca dccb dccc dccl dccs dcdb dcds dcls dcsc dcss dddd ddlc ddss dkba dkdc dlab dlbd dlcs dsac dsba dsbc dscc dscs dsda dsls dssa dssc kaaa kaab kaak kaal kaas kaba kabb kabc kabd kacb kacc kacd kacl kacs kad- kada kadd kadl kads kaka kakc kakk kaks kala kalb kalc kald kalk kall kals kas- kasa kasb kasc kask kasl kass kbaa kbab kbac kbad kbak kbal kbas kbba kbbb kbbc kbbd kbbk kbbl kbbs kbca kbcb kbck kbcl kbcs kbdb kbdl kbds kbkb kbkk kbkl kbla kblb kbld kbll kbls kbsa kbsb kbsk kbss kcaa kcab kcac kcad kcal kcas kcba kcbc kcbd kcbk kcbl kcbs kcca kccb kccc kccd kcck kccl kcda kcdc kcdd kcds kckc kckk kckl kcla kclc kclk kcll kcls kcsa kcsb kcsc kcsd kcss kdaa kdab kdac kdad kdak kdal kdbb kdbl kdbs kdca kdcc kdcd kddb kddc kddd kddk kddl kdka kdkb kdkd kdkk kdla kdlb kdlc kdld kdll kdls kdsc kdsd kdsk kdsl kdss kkaa kkac kkal kkba kkbb kkbd kkbl kkbs kkcb kkcd kkck kkcl kkcs kkda kkdc kkdd kkdl kkkk kklb kklc kkld kkll kkls kksa kksd kkss klaa klab klac klad klak klal klas klbb klbc klbd klbl klbs klca klcb klcc klcd klck klcl klcs kldc kldd klds klka klkc klkk klkl klks klla kllb kllc kllk klls klsa klsc klsd ksab ksac ksak ksal ksas ksba ksbc ksbl ksbs ksca kscb ksck kscl kscs ksdc ksdk ksdl ksds kska kskb kskd kskk ksks ksla kslb kslc ksld kslk ksll kssa kssl ksss laaa laac laad laak laal laas laba labs laca lacc lack lacl lacs lada ladd